FUEL FOR THE LIVING MACHINE 



The food is the fuel which runs our living machine, just 

 p , p . as truly as coal is fuel for an engine. Ex- 

 periments in physiological laboratories have 

 shown that in a man, as in any other well-made machine, 

 you get out an amount of work and heat that corresponds 

 directly to the amount of fuel put in. 



Our first food need, then, is for a sufficient supply of 

 energy. Food energy is measured in calories, one calorie 

 being the amount of heat energy necessary to raise the 

 temperature of one kilogram (about two pints) of water 

 one degree on the centigrade thermometer. Three large 

 lumps of sugar, one large banana, one very large egg, one 

 chop, two thin slices of bread, two apples, one pat of butter, 

 two-thirds of a glass of milk — each of these food portions 

 contains about 100 calories. The average adult needs about 

 2,500 calories a day if leading a sedentary life, 3,000 calories 

 if engaged in active physical work. 



The individual soldier has his dietary needs cared for by 

 those in authority. For the civil population and for the 

 nation as a whole, however, the question of the food supply 

 is a vital one in war time, and particularly at the present 

 moment when the food supplies of Europe are exhausted and 

 the whole allied world depends on America to preserve it 

 from starvation. 



The attainment of proper national dietary standards de- 

 _ . « pends partly on the available food supply 



Q 1 . f and partly on the intelligent selection and 



TV t use °^ f°°d s - The cost °^ 100 calories in 



different forms varies enormously; and by 



learning to make an intelligent selection every individual 



purchaser and every individual householder can help in the 



great task of food conservation. 



The following table, from "The Fundamental Basis of Nu- 

 trition/ ' by Graham Lusk, shows the cost of 1,000 calories in 



6 



